Lung thermography during the initial reperfusion period to assess pulmonary function in cellular ex vivo lung perfusion

Abstract

Background: Thermography is a noninvasive technology to detect low temperatures in poorly circulated areas. In ex vivo lung perfusion (EVLP), lungs are rewarmed to body temperature during the initial 1 h. Currently, the effect of graft thermal changes during the rewarming phase on pulmonary function is unknown. In this study, we evaluated the correlation of lung surface temperature with physiological parameters, wet/dry ratio, and transplant suitability in Lundtype EVLP.Methods: Fifteen pigs were divided into three groups: control group (no warm ischemia) or donation after circulatory death groups with 60 or 90 min of warm ischemia (n = 5, each). Thermal images of the lower lobes were continuously collected from the bottom of an organ chamber using infrared thermography throughout EVLP.Results: At 8 min, lung surface temperatures of nonsuitable cases were significantly lower than in suitable cases (25.1 ± 0.6 vs. 27.8 ± 1.2°C, p < 0.001), while there was no difference in lung surface temperatures between the two groups at 0-4 min and 12-120 min. There was a significant negative correlation between lung surface temperatures at 8 min and wet/dry ratio at 2 h in the lower lobes

Real-time Lung Weight Measurement During Cellular Ex Vivo Lung Perfusion: An Early Predictor of Transplant Suitability

“…In our previous report, the lung surface temperature of injured lungs did not increase as rapidly as that of normal lungs during the initial rewarming phase with a flow of 0.2 L/min because of poor perfusion. 12 Second, the normalized lung weight gain was greater in the evaluation phase than in the recondition phase. Moreover, normalized lung weight gain was highest at evaluation when FiO 2 was 1.0.…”

“…initial rewarming phase with a flow of 0.2 L/min because of poor perfusion. 12 Second, the normalized lung weight gain was greater in the evaluation phase than in the recondition phase. Moreover, normalized lung weight gain was highest at evaluation when FiO 2 was 1.0.…”

“… 14 , 15 The EVLP circuit consisted of an organ chamber, a reservoir, a centrifugal blood pump, a membrane oxygenator, a heat exchanger, and a leukocyte filter as shown in previous reports. 11 , 12 The circuit was primed with 2.0 L of STEEN solution, heparin 10 000 IU, imipenem 100 mg, and 500 mL of packed red blood cells. A pulmonary artery cannula was connected to the circuit.…”

“…Some cases in this study were used in other studies. 11,12 Animal Preparation Males (42-49 kg) crossed between Landrace and Large White pigs were used. Following injection of xylazine (2 mg/kg) and ketamine (20 mg/kg), endotracheal intubation and mechanical ventilation were started.…”